Fabrication and evaluation of stable micro tubular solid oxide fuel cells with BZCY-BZY bi-layer proton conducting electrolytes

摘要

Anode-supported proton conducting micro tubular solid oxide fuel cells (MT-SOFCs) with the configuration of Ni-BaZr_(0.1)Ce_(0.7)Y_(0.2)O_(3-δ) (BZCY)/BZCY/BaZr_(0.8)Y_(0.2)O_(3-δ) (BZY)/ La_(0.6)Sr_(0.4)Co_(0.2)Fe_(0.8)O_(3-δ) (LSCF)-BZY have been prepared by a combination of phase inversion method and suspension-coating technique. The obtained Ni-BZCY anode hollow fiber presents a special asymmetrical structure consisting of a sponge-like layer and a finger-like porous layer, which is propitious to anode electrochemical process. Bi-layer electrolytes consisting of 5 μm thick BZCY and 3 μm thick BZY are successfully fabricated by suspension-coating technique. BZY electrolytes are placed at the cathode side, in order to improve the chemical stability against CO_2. The considerable electrochemical performance and good stability in the presence of CO_2 indicate that the construction of BZY-BZCY bi-layer electrolytes is an effective way for the development of stable proton conducting MT-SOFCs.